Pattern density ray approximating reflector



Jan. 3, 1950 1. J. BARBER 7 2,492,946

PATTERN DENSITY RAY APPROXIMATING REFLECTOR Filed Oct. 11, 1945 floating axis.

Patented Jan. 3, 1950 UNITED STATES PATENT ornca PATTERN DENSITY RAY APPROXIMATING REFLECTOR Ira J. Barber, Fostoria, Ohio," assignor to The Fo storia Pressed Steel Corporation, Fostoria, Ohio, a. corporation of Ohio Application October 11, 1545, Serial No. 621,769

. 3 Claims. 1

This invention relates to approximating symmetrical or uniform density for a ray pattern from a reflector, which in association with the energy source is in the range of the dimension of the projected bounds of the reflector.

This invention has utility when incorporated in conjunction with an incandescent lamp or electric bulb, preferably of a clear glass wall and .the filament localized in a plane transverse of the axis of the bulb. The axis of the bulb desirably is coincident with the axis of the reflector; the reflector having its bounds slightly outward from the plane of the filament to allow for direct rays clear of the reflector in the range of 160". In providing the reflectors as a gang to abut or adjoin at straight line sides in register,

for an aligned square, assembly, the dished reflectors have a concentric central region, disclosed as parabolic on a minus or eccentric focal Toward the corners, extended radial distances are two pitched reflector face regions to have the diagonals of the squaresof the reflectors provide faces to develop ray density approximating that of the face regions toward the midpoints of the sides of the squares of the reflectors.

An advantage practice has to 'do with the treatment of objects of work not at all times planar toward a reflector bank, For instance the work may pass thru a reflector walled tunnel or treatment region. Offset or end portions of the objects, under the disclosure herein, may have a region face at right angles to the plane of .the reflectors receive a ray treatment up to 86% or more of that of a flat face of work at equal distance or spacing from the outer the reflectors.

Referring to the drawings: Fig. l is a view, looking into a gang or panel of reflectors configured under the invention herein; Fig. 2 is a view, with a portion broken away,

plane face of "of a reflector unit or section;

Fig. 3 is a section on the line III-III, Fig. 2, showing the dished configuration of the reflector along a diagonal;

Fig. 4 is a section on the line IVIV, Fig 2, showing the dished configuration of the reflector along a diameter at right angles to the midpoint of the side of the square'reflec'tor;

Fig. 5 is a polar diagram from. an energy source in a reflector unit, in solid line as to the minimum diameter and broken or dotted line as :to the diagonal asto ray density;-

Fig. 6 is a linear diagram from an energy source in a reflector unit, insolid line as to the minimum diameter and broken line as to the diagonal, illustrating the symmetry approximation for ray density pattern to extenduniformly thruout an area exposed for treatment; and

Fig. 7 is a fragmentary view of a further ent ,croachment on the major or central parabolic reflector area, contoured to further supplement ray projection in the region diagonals of adjacent reflectors may intersect.

In a socket I may be mounted an incandescent .bulb.2 having a filament 3, say of M form to lie in a plane transverse to the axis of the bulb 2 and socket l. J

For the bulb 2 to protrude therethru, a rec tangular reflector is provided with a central opening 5, as a throat with slight clearance as to the bulb 2. A desirable contour hereunder as adapted to 250 watt type of infrared ray style of bulb, has a major central parabolic face area 5 contoured from a floating focus 6 in the range of deficient diameter, or rather focal radius. This means that in developing the face 5, such is from a focal point nearer the portion of the face 5 beingdeveloped by a radius thru the axis 1 of the socket l and the axis of thebulb 2. Upon this basis, there is developed a square reflector of A flat bounds, with the outer edges 11" long.

The A flat bounds 8 establish a plane below which l"- in the location of the filament 3,,de-

termines a range of approximately 160 for ray emergence from-the filament 3 clear of the reflector to pass over the bounds 8 andoutward therefrom. This 1" drop back of the plane of the bounds 8 is used to determine a trough base region 9 on the respective, to l" radius, .arc corners IIJ having an inward pitch of about 45. 3 off the diameter, arcs of 1 /8" radius initial a blunt end lobe-portion H for the four diametrical portions of the face 5. Tangential with the adjacent side of the lobe portion H, a riser line extends up from the junction of the region 9 with the lower in-taper of the corner II], to provide upward therefrom toward the planet diverging narrowing V- or wedge-shaped reflectorv faces 12 of longer radial distance than the face portions 5, ll. From mid diagonal region 9, between the face 5, H, and the faces I0, I2, is region 53. While the region 9 is parallel to the plane 8, the region l3 as rising each way therefrom is of just such outward pitch to be under the line of the direction of direct rays to the faces 12. This means that the edges of the regions i3 as joining the faces 5, H, has a somewhat greater spacing thruout than the line of junction between 'the face l2 and the outer edge of the region l3. The contour relation set up as made possible say at 10' outward spacing from the plane of the bounds 8, to develop approximate constant or uniform ray density in the identical 11' square area of thereflector with the complementary advantage of the 160 direct rays from the energy source.

-.-A polar-diagram (Fig; 5) 011a 10 radius from the axis T junction with the reflector 8, inthe direction of a diameter has a graph M. The 180 has .concentriczcircles at 100 F; intervals. A dotted or broken line graph l discloses the temperature readings at from the axis 1 in the plane 8 of the reflector bounds, taken along a diagonal.

A linear diagram graph I6 (Fig. 6) at 10' out-1 ward from the plane of the bounds 8 on a diameter has its high and directias Well aslreflective region between the axis 1 and region I I 'as at the edge of the bounds 8. Diverging direct, as well as possible other stray rays are outward-from the In practice such line i as beyond the line H. out-region is in the high or direct for the ad jacent reflector Lmit, whereby these may combine .from a line I as the companion reflector axis to dergoing service attention, extreme refinement may be achieved to: pickup or. work-out, sa a corner diagonal which may. be short of ray intensity, by proportioninga rib 2! (Fig. 7), in

taking from the normal .fface region of the lobe II. to supplement the arc face In of. the corner. The ordinates on the linear graph, for the 250 watt bulb of the specificexample taken, have the high inthe range. of 400 F, andthe low around 220 for the-solid or. unbroken graph l 6.

The mounting .for. the .bulb socket I may be adjustable, thereby'to shift the position for the filament away from the line of the plane..determined 'by theregions 9. In the instance this adjustment be to .bring the filament 3 intothis plane, there is more close approximation for the ray control as set forth. A departure as inward,

would mean less range of direct rays to clear the reflector unit; while. contrariwise,.a thrusting of the. filament 3 to a position, even tho slight, outward from the regions 9, increases the proportion of direct rays not acted upon by the reflector.

Due to clear glass bulb and 160 ray proportion clear of the reflector unit, an object of work at aparallel plane region according to Fig. 6, would, for a local region at identical spacing, but perpendicular. thereto, have such face ray treated at the range of 86% or more of that 100%, Fig. 6.

The course. taken withthe' focal point 6 to describe a circle forlonger focal distance across the axis '1, may bexconsidered as flattening the" parabolic reflector face portions 5, H. The concave region of the reflector face 5 has encroachment thereupon to the filament plane region 9 as on the diagonals. The corner face portions in as. inwardlyslanting from the plane 8,.determine from this slant, andas outward from the region 9,slight 'outwarddivergence for. the projected rays to fill in the..corner intersection regions of the diametrical abutting reflectors.

The faces I 2 as fairing out in mergingto tangential relation with the. lobes 1|.as diverging from the lobes, widenout to the corners .ll] in conjunction with the inward slant. Under this combination,.the face 12 replenishes the ray decrease toward the corner spacing. While the diagrams as discussed are at the limits, diametrical and diagonal, these faces [2 cooperate for approximation of uniformity in the ray density of the pattern at all angles thru the axis! of the reflector '-unit.-

The offset to the faces 12 from the face 5, locates thee-region l3 asxof relatively: negligible reflective value, with the filament 3 in the plane of the regions 9. Should there be an adjustment of the filament outward, thus to bring the filament 3 above'thecray line as clearing the face 5 to-provide a face short of the face I2, additional rays therefrom may. be directed to the fill-in portions ofjthe' spaced corners.

Thehybrid features are present in the eccentric or flattened parabolic reflector face region 5,! as well'asinthe offset regions [0, l2, and in thecase region I3 may function.

What is claimed andit is desired to secure by Letters Patent is:

1. For alight energy source; a projecting'reflector of closed figure straight edge regionsand connecting corners'defining a planeflthere being a centralopening thru the reflector for the light -energy source to be there mounted and protrude into the reflector, said reflector 'having a concentrically concavemajor .face from' the. opening vrith'portions of said face approaching mid portions 'of the straight edge regions, diverging fromsaidmid portions there being minor. faces more steep from said plane than the majorface, converging pairs'ofsaid'min'or' faces being conwanted 'at the corners bytapering concave portions.

2. For a 'light' source .to .be assembled therein, a projecting reflector of closed straight edge regionsand connecting corners defining a first plane,.there being arcentral opening in the reflector out 'of which. a light. source as there mounted may extend, there being a throat atsaid opening approximating a.second plane parallel to the first plane, said reflector having concentrically of said opening. and .rising from the second plane a concave major fac of greater radial extent sections toward'mid portions .of the straight edge regions andlesser radial extent sections therebetween toward the corners,.and offset regionsoutward fromtthe lesser radial sec.- tionstoward the corners, said offset regions .be-

ingalongradial lines from the corner therefor toward the .openingand along adjacent. lines parallel to said radial lines "with said radial and adjacent parallel lines approaching parallelism tosaid first plane.

SJA. peripherallyisquare symmetrical bowl type of projecting reflector having the square sides and corners in a plane, a majorconcave concentric reflector face symmetrically extending toward mid portions of thesides with offset regions toward and short-of extending to the corners, there being from the corners inwardly tapering. minor reflector faces-from the plane to the offset regions.

IRA. J. BARBER:..

REFERENCES CITED The following i'eferencesv are of record inthe file of this patent-:.

UNITED STATES "PATENTS I Number. Name Date 1,189,231 Benjamin. July 4, 1916 1,658,265 Thompson- Feb. 7, 1928 1,751,070 Boots et al-.-' Mar.18,-l930 2,242,590 Moreau May 20, 1941 2,257,366 Bates et al Sept. 30, 1941 2,266,190 Giese Dec. 16, 1941 2,275,560 Saaf Mar. 10, 1942 

